Fort McCoy Army Base in Wisconsin identified a case of the measles this week as it brings in thousands of Afghan refugees as part of the mass evacuation effort in the wake of the Taliban takeover of Kabul.
An internal government email, viewed by Fox News, said that the base confirmed a case of the measles on Sunday.
"All those who had been in contact with the infected person at base have been isolated, and post-exposure prophylaxis and inoculations are in process," the notice said.
Separately, a senior U.S. government official confirmed to Fox News that officials identified a single measles case as part of what they called a robust health screening process.
The Centers for Disease Control (CDC) describes measles as a "highly contagious" virus that can be spread by coughing, sneezing, and by people breathing contaminated air or touching infected surfaces and then their faces.
It says that the virus is so contagious that if one person has it, up to 90% of the people close to that person who are not immune will also be infected, and that the virus can live for up to two hours in an airspace even after an infected person leaves the area.
According to the CDC, Afghanistan has the seventh highest number of measles cases in the world.
The document said that due to the disease's contagious nature, Fort McCoy was not receiving evacuees "at this time" and was working to procure the necessary vaccines. However, a spokesperson for Task Force McCoy said that the base was still accepting Afghans, of which it can support 13,000.
The spokesperson told Fox News that they were not authorized to provide specific medical cases, but said that "the health of the Afghans at Fort McCoy is a top priority" and that Afghans are given medical screening and immunizations as needed.
The case comes amid continuing concern about the health risks related to the evacuation. The New York Times reported that among the refugees who arrived at Dulles Airport on Aug. 29, officials found six positive cases for COVID-19.
A Department of Homeland Security fact sheet about Operation Allies Welcome says that all arrivals are being tested for COVID-19, and have the chance to receive a COVID-19 vaccine, as well as other vaccines, at no cost.
The Pentagon said last month that it is opening more military bases to hold up to 50,000 Afghan nationals who are either applying for Special Immigrant Visa (SIV) status or are deemed to be "at risk."
The U.S. is opening up Marine Corps Base Quantico in Virginia, Fort Pickett in Virginia, and Holloman Air Force Base, New Mexico to provide support to the U.S. mission to evacuate SIV applicants and other individuals deemed at risk.
That is in addition to Fort McCoy, as well as Fort Lee in Virginia, Fort Bliss in Texas, and Joint Base McGuire-Dix in New Jersey.
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